Cancer remains the number two cause of mortality in the United States, resulting in over 500,000 deaths per year. Despite advances in detection and treatment, cancer mortality remains high. New compositions and methods for the imaging and treatment (e.g., therapeutic) of cancer may help to reduce the rate of mortality associated with cancer.
Severe, chronic pain is observed a variety of subjects. For example, there exist large numbers of individuals with sever pain associated with arthritis, autoimmune disease, injury, cancer, and a host of other conditions.
A vast number of different types of pain medications exist. For example, a number natural and synthetic alkaloids of opium (i.e., opioids) are useful as analgesics for the treatment of severe pain. However, a number of severe side effects associated with opioid and other pain medication usage exist. For example, administration of opioid agonists often results in intestinal dysfunction due to action of the opioid agonist upon the large number of receptors in the intestinal wall. Opioids are generally known to cause nausea and vomiting as well as inhibition of normal propulsive gastrointestinal function in animals, resulting in side effects such as constipation.
Pain medication (e.g., opioid)-induced side effects are a serious problem for patients being administered pain medications (e.g., opioid analgesics) for both short term and long term pain management. For instance, more than 250,000 terminal cancer patients each year take opioids, such as morphine, for pain relief, and about half of those patients experience severe constipation. At present, patients receiving opioid pain medications face the difficult choice of suffering burdensome adverse effects (e.g., constipation) or ineffective analgesia.
There exists a need for compositions, methods and systems for delivering agents (e.g., diagnostic and/or therapeutic (e.g., cancer and/or pain therapeutics) to subjects that provide effective therapy (e.g., disease treatment, symptom relief, etc.) with reduced or eliminated side effects, even when administered in high doses.